Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin

Journal of Hydrology
By: , and 



Study region

The study region encompasses the Upper Colorado River Basin (UCRB), which provides water for 40 million people and is a vital part of the water supply in the western U.S.

Study focus

Groundwater and surface water can be considered a single water resource and thus it is important to understand groundwater contributions to streamflow, or baseflow, within a region. Previously, quantification of baseflow using chemical mass balance at large numbers of sites was not possible because of data limitations. A new method using regression-derived daily specific conductance values with conductivity mass balance hydrograph separation allows for baseflow estimation at sites across large regions. This method was applied to estimate baseflow discharge at 229 sites across the UCRB. Subsequently, climate, soil, topography, and land cover characteristics were statistically evaluated using principal component analysis (PCA) to determine their influence on baseflow discharge.

New hydrological insights for the region

Results suggest that approximately half of the streamflow in the UCRB is baseflow derived from groundwater discharge to streams. Higher baseflow yields typically occur in upper elevation areas of the UCRB. PCA identified precipitation, snow, sand content of soils, elevation, land surface slope, percent grasslands, and percent natural barren lands as being positively correlated with baseflow yield; whereas temperature, potential evapotranspiration, silt and clay content of soils, percent agriculture, and percent shrublands were negatively correlated with baseflow yield.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin
Series title Journal of Hydrology
DOI 10.1016/j.ejrh.2015.04.008
Volume 4
Issue B
Year Published 2015
Language English
Publisher Elsevier
Contributing office(s) Utah Water Science Center
Description 17 p.
First page 91
Last page 107
Country United States
State Arizona, Colorado, New Mexico, Utah, Wyoming
Other Geospatial Upper Colorado River Basin
Online Only (Y/N) N
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
Additional publication details